Buffer overflow in Cesanta Mongoose

CVE-2026-5244

A vulnerability has been found in Cesanta Mongoose up to 7.20. This affects the function mg_tls_recv_cert of the file mongoose.c of the component TLS 1.3 Handler. Such manipulation of the argument pubkey leads to heap-based buffer overflow…

Vulnerability class: Buffer Overflow

EPSS: 0.001 (27.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.3 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-5244?
CVE-2026-5244 is a high-severity vulnerability in Cesanta Mongoose, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 7.3/10. Published 2026-04-02.
How severe is CVE-2026-5244?
High severity. CVSS v3 base score is 7.3 out of 10.